In a known method for monitoring a thermodynamic process in an installation, in which images of the process are produced and subjected to image evaluation, first specific features for image evaluation are defined which appear to be promising to the operator of the installation for modeling the process. For example, one defines specific moments and then reproduces the image material on this, necessarily reduced, system of functions. The selected features, and only these, are then examined and used for creating a process model. Optionally, only parts of the information contained in the image material are extracted and used.